[quicknir]

I didn't intend to imply otherwise but I see my wording was unclear. I meant that D generally would be a hit, though it's only really speculation either way.

[WalterBright]

There is no inherent reason that D code would be slower than C++ code.

I should know, I've written a C++ compiler and know where the bloat is buried, and designed D to eschew features that would be inherently slower than the C++ counterparts.

You can even turn off the runtime array bounds checking.

[p0nce]

If you use the same backend... no. They are both native languages with "no room below".

llvm vs icc could be a hit, but that's all really.